Leather sole channeling and stitching machine



July 28, 1936. H. CORRALL ET AL LEATHER SOLE CHANNELING AND STITCHING MACHINE Filed June 23, 1934 2 Sheets-Sheet 1 He rberi Corrall and 34 /0 E c 33 33 3 2 .5. F166.

FI JZFIQ James Heg ie Patented July 28, 1936 LEATHER s STITOHIN Herbert Corrall, Hele PATE oLE CHANNELING AND G MACHINE nsburgh, and James Heggie,

2,049,408 NT Fries Clydebank, Scotland, assignors to The Singer Manufacturing Company,

Elizabeth, N. J., a

corporation of New, Jersey I Applic 9 Claims.

This invention relates to sewing machines, particularly for stitching soles of footwear, comprising a leather ply and a felt ply, and aims to provide an improved construction for channeling the leather ply and stitching in the same operation.

In the machine accordin channeling is effecte which engages the lea leather ply ply overlying the throat gageable by the feed dog.

g to the invention the d by a stationary knife ther ply of the sole, the being located uppermost and the felt plate so as to be en- The sole of the presser foot conveniently comprises interconnected between them a fixed channe located immediately in fro ture in the presser foot.

knife blade is concaved 'so as for the needle which is thus gui sections point of cut. The knife blade is serving to clamp ling knife blade nt of the needle aper- The rear face of the to afford a guide ded close to the of arcuate form and adjustable in the vertical plane containing the line of cut.

For feeding the work there is employed, in

addition to under feedi a feed dog, an upper fee by a feed slide carrie operatively connected rock shaft, whereby the fe ng mechanism including ding element constituted by the presser foot and to the usual lower feed ed slide is reciprocated' parallel to the plane of the work in contact with antifriction bearing members received in a raceway in the With the described leather ply, and even knife is effected.

under side of the presser foot.

arrangement there is no tendency to drag the felt ply and clean cutting by the away from the In the accompanying drawings Figs. 13 show feeding mechanisms, of a sewing machine embodying the present inventhe upper and lower tion, Fig. 1 being an elevation in a plane parallel to the line of feed, Fig. 2 a part planpart horizontal section on the Fig. 3 a part front eleva tion on the line b-b mentary plan, part horizon the throat plate, the feed slide,

the channeling knife;

line a- -a of Fig. 1, and tion part vertical secof Fig. 1; Fig. 4 is a fragtal section, showing the feed dog, and

are detail views of the knife blade, Fig. 5 being a side elevation,

Fig. 6 an elevation viewe feed, Fig. '7 an elevation viewed direction, Fig. 8 an enlarged horizontal section on the line c-c of d in the direction of in the opposite Fig. 5, and Fig. 9 an inverted plan view of the lower or operative end of the blade.

Referring to the of the sewing machine brac drawings; 1 denotes the head ket arm in which are journalled the reciprocatory needle-bar 2 and the usual spring-depr presser-bar being adap operation of the lifter lever 3'.

essed presser-bar 3, said ted to be lifted by manual 4 denotes the throat plate provided with feed-slots for passage of theusual feed-dog 5 and with the needle aperture 6 for passage of the needle I clamped to the needle-bar 2 and'co-operating with a lower stitch-forming instrument, as for instance a loop-taker moving in' the circular path 7 below the work. 8 denotes the feed rock shaft of the usual under feeding mechanism for imparting four-motion movements to the feed-dog 5, which receives rising and falling movements from the feed-lift rock-shaft 8'.

The presser foot 9 is secured to the lower end of the presser-bar 3 and carries a channeling knife blade lEi located immediately in front of the needle I viewed in the direction of feed and adapted to cut an inverted T-shaped channel H in the leatherv ply 12 of a footwear sole having also a felt ply l3to be stitched to the leather ply l2 by stitches laid in the channel H so formed.

In the stitching operation the felt ply l3, being undermo-st, is engaged by the feed-dog 5, whereby the sole is fed beneath the needle.

M denotes an upper feeding element constituted by a feed-slide located beneath and carried by the presser foot'9, being attached at its rear end to a carrier member l5 slidable on a guide bar it fitted to and extending rearwardly of the presser foot 9, whereby the feed-slide is confined to horizontal reciprocatory movements.

As shown, the feed-slide I4 is formed with a central cut-away I! to clear the needle I and the channeling knife Ill.

The presser foot 9 bears on the feed-slide l4 through the medium of ball bearings 18 accommodated in a raceway l9 formed in the underside of the presser foot and extending parallel to the line of feed.

.The feed slide actuating mechanism comprises a short link 20 pivotally connected at one end at 2! to the carrier member 55 and pivotally connected at the other end at 22 to an arm 23 secured. on one end of a horizontal rock shaft 24 journalled in a bracket25 rising from the bedplate 25 of the machine. 'On its opposite end the rock shaft 24 carries an arm 2'! the bifurcated lower end 28 of which is operatively engaged by a roller'29 adjustably mounted in an arm 36 secured on the feed rock shaft 8 and projecting upwardly through a slot 3l'in the machine bedplate 26.

In operation, the feed-dog 5,-the feed-slide l4, and the work l2, l3 advance together, the ball bearings l8 permitting the feed-slide Hi to move forwardly with minimum frictional resistance, the feed-slide I l sliding over the work in its return movement.

arcuate metallic blade, of approximately isosceles triangular shape in radial section, disposed in a vertical plane parallel to the line of feed, the apex of the triangle formed by a radial section of the blade projecting forwardly or opposite to the direction of feed, and cave front edge of the blade. The lower end portion of the blade is shaped to present two lateral cutting edges 32 disposed in a horizontal plane and diverging in the direction of feed away from a front vertical cutting edge 33. The knife projects below the feed-slide M to an extent depending on the depth of the channel II to be cut in the leather ply I2, it being understood that the cutting edges 32 and 33 will cut a channel I I of inverted T-shape in cross section in the leather ply i2, said channel H being held open until the stitch is formed and closing automatically when the work passes beyond the stitching point. Formed in the rear face of the knife blade is a peripheral groove 34 the lower portion of which defines the forward boundary of a needle aperture 35 in the presser foot 9 and which serves to guide the needle close to the Work.

The knife blade is adjustably clamped to the presser foot 9 by means of a clamp element 35 forming part of the presser foot and defining therewith a knife-receiving socket 31. The clamp element 36 is secured to the presser foot by means of a stud 38 penetrating the forward end of the presser foot and engaged by a nut 3 adjustable to permit adjustment, removal, and replacement of the knife blade. The clamp element 36 is also provided with a dowel pin 40 engageable with a socket 4| in the presser foot.

As will be understood, by slackening back the nut 353, the knife blade It! may be adjusted circularly in its socket 31 whereby to vary, within narrow limits, the distance which the cutting edges 32 project below the feed-slide l4.

Due to the arcuate form of the blade ,lll tangent to the needle-path'there is no possibility of the upper portion of the blade being fouled by the needle clamp 1' in the descent of the needle 1.

42 denotes a work guide roller overhanging the throat plate 4.

We claim:

1. In a sewing machine, in combination, a presser-foot above the work, under feeding mechanism including a feed-dog engageable with the under side of the work beneath said presser-foot, and a work-engagingfeed-element engageable with the upper side of the work, said feedelement being located beneath and carried by and movable relative to said presser-foot and participating in the feeding movements of said feed-dog.

2. In a sewing machine, in combination, a presser-foot above the work, under feeding mechanism including a. feed-dog engageable with the under side of the work beneath said presserfoot, a work-engaging feed-slide located beneath said presser-foot, means for supporting and guiding said feed-slide by said presser-foot, and means operatively connecting said feed-slide with said under feeding mechanism. v

3. In a sewing machine, a presser-foot above the work, under feeding mechanism including a feed rock-shaft and a four-motion feed-dog operatively connected to said rock-shaft and engageable with the under side of the work, an arm on said shaft, a feed-slide movable beneath said presser-foot and engageable with the upper side of the work, guiding means for said feed-slide whereby said feed-slide is confined to reciprocabeing located at the cona and means operatively tory movements parallel to the plane of the work, an upper rock-shaft, and depending arms on said upper rock-shaft, one of said depending arms being linked to said feed-slide,and the other depending arm being operatively connected with said first mentioned arm.

4. In a sewing machine, in combination, a presser-foot above the work, under feeding mechanism including a feed-dog engageable with the under side of the work beneath said presser-foot, a work-engaging feed-slide located beneath said presser-foot, means for supporting and guiding said feed-slide by said presser-foot, anti-friction bearing members interposed between said feedslide and the under side of said presser-foot, connecting said feed-slide with said under feeding mechanism.

5. In a sewing machine, in combination, a presser-foot formed on its under side with a ball race, balls received in said ball race, under feeding mechanism including a feed-dog engageable with the under side of the work beneath said presser foot, and a Work-engaging feed-slide engageable with the upper side of the work, said feed-slide being carried by said presser-foot in engagement with said balls and participating in the feeding movements of said feed-dog.

6. In a machine for simultaneously channeling and stitching material, in combination, stitchforming means including a reciprocatory needle, a presser-foot engageable with the upper side of the work and having a needle aperture, mechanism for feeding the work to and past the needle, and a work-channeling knife blade of arcuate form mounted in said presser-foot in advance of the needle and having an operative end shaped to form an inverted T-shaped channel in the work, the rear face of said blade being grooved to guide the needle close to the work.

'7. In a machine for simultaneously channeling and stitching material, in combination, a presserfoot engageable with the upper side of the work, a work-channeling knife blade of arcuate form mounted for vertical adjustment in said presserfoot and having an operative end shaped to form an inverted T -shaped channel in the work, and mechanism for feeding the work to said blade.

8. In a machine for simultaneously channeling and stitching material, in combination, stitchforming means including a reciprocatory needle, a presser-foot engageable with theupper side of the work and having a needle aperture, mechanism for feeding the work to and past the needle, and an arcuate work-channeling knife blade of triangular form in radial section mounted in said presser-foot in advance of the needle and having an operative end shaped to form an inverted T- shaped channel in the work, the rear face of said blade being grooved to guide the needle close to the work.

9. The combination with stitch-forming mechanism including a reciprocatory needle, of a lower four-motion feed-element, an upper two-motion feed-element, a presser-foot exertingpressure at all times on said two-motion feed-element during a sewing operation, and an upper channeling knife carried by said presser-foot and disposed closely in advance of said needle and having its operative lower end formed with vertical and horizontal cutting edges arranged to cut and open an inverted T-shaped channel in the work for entry by said needle. I

HERBERT CORRALL.

JAMES HEGGIE. 

